The original description page was here. In electronicsa varicap diodeavricap diodevariable capacitance diodevariable vaficap diode or tuning diode is a type of diode designed to exploit the voltage-dependent capacitance of a reverse-biased p—n junction. From Wikimedia Commons, the free media repository. Wikimedia Commons has media related to Varicaps. All following user names refer to it.

Popular makeshift varicaps include LEDs, [5] 1NX series rectifier diodes, [6] Schottky rectifiers and various transistors used with their collector-base junctions reverse biased, [7] particularly the 2N and BC Separation of grounds is often done to i prevent high-frequency radiation from the low-frequency ground node, and ii prevent DC currents in the AC ground node changing bias and operating points of active devices such as varicaps and transistors.

This page was last edited on 13 Novemberat Some designs of electronic security tag readers used in retail outlets require these high capacitance varicaps in their voltage-controlled oscillators.

Potentiometer digital Variable capacitor Varicap. Retrieved from ” https: I, the copyright holder of this work, hereby publish it under the following license:. They are often used in pairs to switch between two different RF sources such as the VHF and UHF bands in a television tuner by supplying them with complementary bias voltages. They are commonly used in voltage-controlled oscillatorsparametric amplifiersand frequency multipliers.

When in the high capacitance state, usually with low or no bias, they present a low impedance path to RF, whereas when reverse biased their capacitance abruptly decreases and their RF impedance increases. The DC bias variicap must be blocked from entering the tuned circuit.

File:Diodo – Wikimedia Commons

Varicap diode Internal structure of a varicap. Maximum reverse bias voltage is usually between 5 and 7 Volts, dioddo the avalanche process starts conducting. Internal structure of a varicap. This work has been released into the public domain by its author, Example at the [[:: This helps explain the different names for the device as it came into use.

File:Varicap symbol.svg

By using this site, you agree to the Terms of Use and Privacy Policy. From Wikimedia Commons, the free media repository.

Generally the use of a varicap diode in a circuit requires connecting it to a tuned circuitusually in parallel with any existing capacitance or inductance. Date and time of digitizing lun varjcap lug Special types of varicap diode exhibiting an abrupt change in capacitance can often be found in consumer equipment such as television tuners, which are used to switch radio frequency signal paths.

September Learn how and when to remove this template message. The figure shows an example of a cross section of a varactor with the depletion layer formed of a p—n junction.

Summary [ edit ] Description Diodo Varicap. Varicaps in various packages. Simbolo circuitale di un diodo varicap. These types were — and still are — extensively used in television tuners, whose high carrier frequencies require only small changes in capacitance. This depletion layer can also be made of a MOS or a Schottky diode.

By using this site, you agree to the Terms of Use and Privacy Policy. In other projects Wikimedia Commons. A third circuit, at top right in diagram, uses two series-connected varicaps and separate DC and AC signal ground connections.

This website uses cookies to improve your experience. We'll assume you're ok with this, but you can opt-out if you wish. Cookie settingsACCEPT

Privacy & Cookies Policy

Privacy Overview

This website uses cookies to improve your experience while you navigate through the website. Out of these cookies, the cookies that are categorized as necessary are stored on your browser as they are as essential for the working of basic functionalities of the website. We also use third-party cookies that help us analyze and understand how you use this website. These cookies will be stored in your browser only with your consent. You also have the option to opt-out of these cookies. But opting out of some of these cookies may have an effect on your browsing experience.

This website uses cookies to improve your experience while you navigate through the website. Out of these cookies, the cookies that are categorized as necessary are stored on your browser as they are as essential for the working of basic functionalities of the website. We also use third-party cookies that help us analyze and understand how you use this website. These cookies will be stored in your browser only with your consent. You also have the option to opt-out of these cookies. But opting out of some of these cookies may have an effect on your browsing experience.

Necessary cookies are absolutely essential for the website to function properly. This category only includes cookies that ensures basic functionalities and security features of the website. These cookies do not store any personal information.

Any cookies that may not be particularly necessary for the website to function and is used specifically to collect user personal data via analytics, ads, other embedded contents are termed as non-necessary cookies. It is mandatory to procure user consent prior to running these cookies on your website.